Vulnerability Database

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Total vulnerabilities in the database

CVE-2024-35955 — linux / linux_kernel

Use After Free

In the Linux kernel, the following vulnerability has been resolved:

kprobes: Fix possible use-after-free issue on kprobe registration

When unloading a module, its state is changing MODULE_STATE_LIVE -> MODULE_STATE_GOING -> MODULE_STATE_UNFORMED. Each change will take a time. is_module_text_address() and __module_text_address() works with MODULE_STATE_LIVE and MODULE_STATE_GOING. If we use is_module_text_address() and __module_text_address() separately, there is a chance that the first one is succeeded but the next one is failed because module->state becomes MODULE_STATE_UNFORMED between those operations.

In check_kprobe_address_safe(), if the second __module_text_address() is failed, that is ignored because it expected a kernel_text address. But it may have failed simply because module->state has been changed to MODULE_STATE_UNFORMED. In this case, arm_kprobe() will try to modify non-exist module text address (use-after-free).

To fix this problem, we should not use separated is_module_text_address() and __module_text_address(), but use only __module_text_address() once and do try_module_get(module) which is only available with MODULE_STATE_LIVE.

  • Published: May 20, 2024
  • Updated: Nov 16, 2025
  • CVE: CVE-2024-35955
  • Severity: High
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWEs:

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